PROBLEM TO BE SOLVED: To provide the distal end part of an ultrasonic endoscope reducing the increase in the length of the leading end hard part of the ultrasonic endoscope to the utmost, which is caused by connecting an optical observation part block and an ultrasonic scanning part block in a detachable manner, and reducing the pain received by an examinee.SOLUTION: A cylindrical protrusion part 22, to which a signal wire passing hole 21 for passing the signal wire 19 connected to an ultrasonic probe 13 is formed, is formed to the ultrasonic scanning part block 14 so as to be protruded rearward and a connecting through-hole 23, into which the cylindrical protrusion part 22 is inserted from the front to thrust through rearward, is formed to the optical observation part block 12 so as to pierce therethrough in a direction parallel to the axial line of the optical observation part block 12, and the slip-off preventing ring 25 is provided, which is locked with the vicinity of the rear end part of the cylindrical protrusion part 22 protruded rearward from the rear end of the connecting through-hole 23 in a freely detachable manner to control the slip-off of the cylindrical protrusion part 22 in a freely detachable manner to control the slip-off of the cylindrical protrusion part 22 from the connecting through-hole 23.COPYRIGHT: (C)2010,JPO&INPIT【課題】光学観察部ブロックと超音波走査部ブロックとを着脱可能に連結するために生じる超音波内視鏡の先端硬質部の長さの増大を極力小さくすることができ、被検者が受ける苦痛を減少させることができる超音波内視鏡の先端部を提供すること。【解決手段】超音波プローブ13に接続された信号線19を通過させるための信号線通し孔21が形成された筒状突出部22が超音波走査部ブロック14から後方に突出形成されて、光学観察部ブロック12には、筒状突出部22が前方から嵌挿されて後方に突き抜ける連結用貫通孔23が軸線と平行方向に貫通形成され、連結用貫通孔23の後端からその後側に突出する筒状突出部22の後端部付近に係脱自在に係合して筒状突出部22が連結用貫通孔23から抜けるのを規制する抜け止めリング25が設けられている。【選択図】 図1
